@keyframes _淡入{
    0%{
        opacity:0;
    }
    100%{
        opacity:1;
    }
}
@keyframes _下入{
    0%{
        position: relative;
        top: 50px;
        opacity:0;
    }
    100%{
        opacity:1;
        position: relative;
        top: 0px;
    }
}


@keyframes _淡出{
    0%{
        opacity:1;
    }
    100%{
        opacity:0;
    }
}
@keyframes _黑出{
    0%{
        opacity: 1;
        filter: brightness(100%)
    }
    50%{
        opacity: 1;
        filter: brightness(0%)
    }
    100%{
        opacity:0;
        filter: brightness(0%)
    }
}

.淡入{
    animation:_淡入 0.6s;
    animation-fill-mode:forwards;
}
.下入{
    animation:_下入 0.6s;
    animation-fill-mode:forwards;
}
.灰{
    filter: grayscale();
}
.透明{
    opacity:0.5;
}